A 75-year-old woman with a 10-year history of well-treated hypertension is referred for cardiac assessment for intermittent palpitation, that she describes as the sensation of her heart “beating strong and fast”:

• Atrial flutter with 2 to 1 AV conduction
• Ventricular rate 135/min

The patient was treated with digoxin and a beta-blocker. She became symptom-free, and her exercise tolerance improved:

• Atrial flutter with variable AV conduction
• Ventricular rate 95/min.